Program guide apparatus

ABSTRACT

A method acquires program guide information in an image signal receiver, and program guide method and apparatus using the same. In the program guide apparatus, information immediately required by a user is obtained first, and information of less preferential channels is obtained next, thus presenting a smooth interface to the user. The method of acquiring program guide information for channels includes acquiring the program guide information for each channel by scanning accessible channels while a received program is not displayed. The program guide apparatus includes a tuner tuning a channel, a program guide information detector, a memory, a key input, a microprocessor, and a character signal generator.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application of application Ser. No.09/163,977, filed Sep. 30, 1998, now pending. This application claimsthe benefit of Korean Application No. 98-36628, filed Sep. 5, 1998, inthe Korean Industrial Property Office, the disclosure of which isincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of acquiring program guideinformation in an image signal receiving apparatus, and to a method andapparatus for guiding a program using the same.

2. Description of the Related Art

Generally, program information of a conventional analog TV broadcast issupplied to publications such-as newspapers, TVs, magazines, etc.However, in a digital multichannel broadcast, tens to hundreds ofchannels are provided, so that a total number of the selectionsavailable to viewers becomes larger and simultaneously program selectionis significantly complicated.

In such a digital broadcast, an electronic program guide (EPG) providinga program list or information on the content of each program isintroduced as a fundamental data service.

Current EPG information is transmitted per channel. That is, since theEPG information of a corresponding channel is transmitted per channel,it is difficult to obtain the EPG information of all channels capable-ofbeing accessed.

To be more specific, the EPG information of a current received channelcan be obtained by interpreting additional information included in atransport packet received. However, in order to acquire EPG informationof all channels capable of being accessed, a user must tune all channelsindividually.

In the digital broadcast, many more channels are provided than in theanalog broadcast, and each channel can include subchannels. Therefore,it is important to swiftly interface the EPG information of each channelto a user.

SUMMARY OF THE INVENTION

To solve the above problems, it is an object of the present invention toprovide a method of acquiring useful EPG information.

It is another object of the present invention to provide a program guidemethod appropriate for the above method.

It is still another object of the present invention to provide a programguide apparatus appropriate for the above method.

Accordingly, to achieve the first object, there is provided a method ofacquiring program guide information for channels wherein the programguide information for each channel is acquired by scanning accessiblechannels while a received program is not displayed.

To achieve the second object, there is provided a program guiding methodin which a program list for channels is displayed in response to aprogram guide command. The program guiding method comprises the steps ofacquiring program guide information of accessible channels, storing theacquired program guide information, writing a program list on the basisof the stored program guide information, and displaying the writtenprogram list to the user.

Also to achieve the second object, the step of acquiring the programguide information comprises the steps of writing and displaying aprogram list including program guide information of channels tunedbefore a program guide command is executed, from the stored programguide information, and acquiring program guide information for eachchannel by searching for accessible channels in a background operationwhile the program list is referred to.

To achieve the third object, there is provided an apparatus foracquiring the program guide information of accessible channels andguiding program guide information acquired in response to a programguide command in a multichannel receiver. The apparatus comprises atuner tuning a channel, a program guide information detector, a memory,a key input, a microprocessor, and a character signal generator.

The program guide information detector detects program guide informationintroduced via the tuner. The memory stores the program guideinformation for each channel detected by the program guide informationdetector. The key input introduces a user manipulation command such as aprogram guide command or a channel search command. The microprocessorwrites a program list based on program guide information stored in thememory in response to the manipulation command input via the key inputand is programmed to search for accessible channels by controlling thetuner in a background operation while a user refers to the program list.The character signal generator generates a character signalcorresponding to the program list written by the microprocessor andprovides the character signal to a screen.

BRIEF DESCRIPTION OF THE DRAWINGS

The above objects and advantages of the present invention will becomemore apparent by describing in detail a preferred embodiment thereofwith reference to the attached drawings in which:

FIG. 1 is a block diagram illustrating the configuration of a generalDTV receiver;

FIG. 2 is a flowchart illustrating a method of acquiring program guideinformation, according to the present invention;

FIG. 3 is a flowchart illustrating a program guide method according tothe present invention;

FIGS. 4A through 4C show a program list displayed on a screen in themethod shown in FIG. 3;

FIG. 5 is a block diagram illustrating an embodiment of a program guideapparatus according to the present invention; and

FIG. 6 is a block diagram illustrating another embodiment of a programguide apparatus according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Channel numbers, channel names, program names schedules, etc., generallytransmitted as data are displayed on a TV screen as a program listhaving a time axis and a channel axis by EPG software of a receiver. Auser can perform operations such as tuning or programming in the programlist by manipulating a cursor.

FIG. 1 is a block diagram showing the configuration of a conventionaldigital multichannel TV (hereinafter, called “DTV”) receiver (which isalso used in the present invention, as explained with reference to FIG.2). In FIG. 1, a tuner 102 tunes a radio frequency (RF) channel fromreceived broadcast signals via an antenna 100 under the control of amicroprocessor 124. The tuner 102 outputs an intermediate frequency (IF)signal of the tuned channel, and an IF module 104 outputs a basebandsignal of the tuned channel to a channel decoder 106.

The channel decoder 106 channel-decodes the baseband signal receivedfrom the IF module 104 and reproduces data bit lines. Each of thereproduced data bit lines is divided into audio data, video data, andadditional data by a transport stream (TS) decoder 108.

The audio data is transmitted to an audio decoder 110 and decodedaccording to an MPEG standard or dolby AC-3 standard by the audiodecoder 110. The audio data is processed by an audio processing andoutput unit 112 and output as sound through a speaker 114.

The video data is transmitted to a video decoder 116, decoded accordingto the MPEG standard, applied to an on-screen-display (OSD) mixer 118,mixed with OSD data generated by the, microprocessor 124, processed by avideo processing and outputting unit 120, and output on the screen of apicture tube 122. Here. the OSD data is used for the microprocessor 124to display various information as graphics or text on a screen.

The additional data is transmitted to the microprocessor 124. Themicroprocessor 124 extracts program guide information or otherinformation and stores the extracted information in a memory unit 126.Typical EPG information is stored in a nonvolatile memory such as anEEPROM or a flash ROM.

A key pad 130 and an infra red (IF) receiving unit 134 are connected tothe microprocessor 124, which is a control unit of a DTV receiver, via auser interface 128. The microprocessor 124 performs operations dependingon various operation commands received from an IR remote controller 132via the keypad 130 and the IR receiving unit 134, according to a programstored in the memory 126. Here, the IR remote controller 132 can be awireless mouse such as an air mouse, a remote controller, etc.

A command from the IR remote controller is received as an IR signal bythe IR receiving unit 134, and transmitted to the microprocessor 124 viathe user interface 128. Also, the additional data from the TS decoder108 is transmitted to the microprocessor 124. Here, the additional dataincludes program specific information (PSI) organized as a table withrespect to program associated information prescribed in MPEG-2, and theaforementioned EPG information.

The memory unit 126 includes a ROM for storing the program of themicroprocessor 124, a RAM for temporarily storing data created duringthe program execution in the microprocessor 124, and an electricallyerasable and programmable ROM (EEPROM) for storing various referencedata.

The microprocessor 124 is connected via a bus 136 to the tuner 102, theIF module 104, the channel decoder 106, the TS decoder 108, the audiodecoder 110, the audio processing and outputting unit 112, the videodecoder 116, the OSD mixer 118, the video process and output unit 120,and the memory unit 126.

In the apparatus shown in FIG. 1, while a user selects and receives achannel, the microprocessor 124 detects, the EPG information from theadditional data provided by the TS decoder 108. The EPG information of acorresponding channel is stored in the memory unit 126, and provided toa user in a program guide mode.

Since the EPG information is transmitted separately for each channel,the EPG information of a corresponding channel cannot be acquired ifthat channel is not tuned.

Thus, a program list for all channels cannot be provided in the programguide mode for guiding a program list for each channel to a user, in theconventional apparatus.

In the present invention, while a program of a channel tuned by thetuner 102 is not displayed, for example, while a user selects orprograms a program with reference to EPG information displayed on ascreen or views line input, an accessible channel is scanned in abackground operation, to obtain the EPG information.

FIG. 2 is a flowchart showing a method of obtaining program guideinformation according to the present invention. FIG. 2 shows an exampleof obtaining EPG information in a program guide mode according to thepresent invention, using the conventional apparatus showing FIG. 1.

When a program guide command is input from a user via the keypad 130,the apparatus shown in FIG. 1 enters into a program guide mode. In theprogram guide mode, first, all channels capable of being accessed by thetuner 102 are scanned to obtain program guide information for eachchannel, in step S200. The microprocessor 124 controls the tuner 102 toscan as many channels as possible, and detects the program guideinformation for each channel from additional data introduced via thetuner 102. Here, the accessible channels include not only the channelscapable of being accessed by the tuner 102 but also line input.

Obtained EPG information is stored, in step S202.

The obtained EPG information is stored in the memory unit 126. The EPGinformation is transmitted for each channel, so that the microprocessor124 acquires EPG information of a corresponding channel whenever achannel is changed and stores the acquired EPG information to the memoryunit 126.

According to the method of FIG. 2, when the program guide mode begins,program guide information with respect to all the accessible channels isacquired all at once in an initial stage. Thus, much time is required todisplay the program guide information.

An increase in the number of accessible channels requires a longer timeto display the program guide information, and causes the userinconvenience. In particular, a digital broadcast provides tens orhundreds of channels, thus requiring a lot of time to acquire the EPGinformation of all channels.

To solve this problem, in the present invention, the EPG information ofa prior channel among prioritized channels is first obtained, and theEPG information of a channel having the lowest priority is thenobtained, thus accomplishing a smooth user interface.

The priority of the channel search is determined by the distance(interval) of the channels to the channel tuned before a program guidecommand is executed, or by a probability distribution of channels, i.e.,the accumulation of the number of times which channels are selected.

A typical user searches using a channel up/down command, so it isnatural for the user to search beginning with channels included in acurrently-displayed program list and their closest channels.

Here, the closest channels include upper closest channels and lowerclosest channels, and it is preferable to determine by default whichchannel among the above closest channels is to be accessed first.

Also, it is necessary to change the direction of search according to thecharacteristics of a user, even if the search direction is determined bydefault. For example, even if the default search direction is set to beupward, once the user designates a channel down button, lower channelsmust be preferentially searched. It is preferable that in preparationfor when a user changes the search direction in the middle of a search,a channel search direction is determined referring to a channel up/downcommand or page up/down command received just before determining achannel search.

FIG. 3 is a flowchart illustrating a program guide method according to apreferred embodiment of the present invention. Response must bepreferentially considered in the interface with a user. It is consideredthat a good response is provided if a system quickly responds to acommand input by a user. The response is not considered good if a usermust wait until program guide information for all channels is obtainedafter inputting the program guide command.

However, the user immediately needs program guide information of achannel viewed before the program guide command is executed, and programguide information of several channels adjacent to the channel viewed,not the program guide information for all channels.

In the present invention, the channel viewed before the program guidecommand is executed, and the program guide information of severalchannels adjacent to the above channel are first acquired and displayedto the user, thus improving the response.

Also, channels adjacent to channels displayed in preparation for thechannel search by a user are first searched, and farther channels arethen gradually searched, thus obtaining the program guide information ofaccessible channels.

Referring to FIG. 3, first, it is detected whether program guideinformation of a channel tuned before a program guide command isexecuted is effective, in step S300. Generally, a user executes aprogram guide command while receiving the program of a channel. The EPGinformation of a channel is automatically obtained while that channel istuned, so that at least the program guide information of the channeltuned before the program guide command is executed can be consideredeffective.

In a display step S310, at least a program list of channels tuned beforethe program guide command is executed among stored EPG information isdisplayed. The microprocessor 124 writes a program list includingchannels tuned before the program guide command is executed among EPGinformation stored in the memory unit 126, and provides the program listto the OSG mixer 118. The OSG mixer 118 converts the program listprovided by the microprocessor 124 into a character signal, and displaysthe character signal on a screen.

FIG. 4A shows the contents displayed on a screen as the result of thestep S310. In FIG. 4A, reference numeral 400 is a screen, referencenumeral 410 is a program list, reference numeral 420 is a cursor,reference numeral 430 is an up/down button, reference numeral 450 is apage up/down button, and reference numeral 440 is a left/right scanbutton.

The program list 410 lists a program for each channel on channel andtime axes. Channels listed in the program list 410 are controlled by theup/down button 430, and time is controlled by the left/right scan button440.

A user can search for a channel and time of a desired program, using theup/down button 430 and the left/right scan button 440.

Whenever the up/down button 430 is pressed, a selection bar 460 movesbetween the listed channels. When the selection bar 460 departs from ascreen boundary, the content of the program list 410 is renewed so thatthe next adjacent channel can be displayed.

If program guide information of channels tuned before the program guidecommand is executed is not effective or not stored, a screen displaymessage like “please wait” or “obtaining program guide information” isdisplayed to the user, in step S360. If it takes a short time to obtainthe program guide information of the tuned channel, this message displaystep may be omitted.

Then, program guide information of channels tuned before a program guidecommand is executed is obtained, in step S370. A program list includingthis program guide information is displayed, in step 310.

In a program guide information acquiring step S320, program guideinformation for each channel is obtained by scanning accessible channelsvia the tuner 102 while a user views displayed EPG information.

To be more specific, in the program list shown in FIG. 4, an invertedchannel number in a program list 410 of a channel No. 53 indicates thatchannel No. 53 was viewed before a program guide mode.

In the circumstances where the program list as shown in FIG. 4B isdisplayed, channels are searched to obtain EPG information, in thefollowing sequence.

If a channel No. 52 is in an upper adjacent screen boundary 480 and achannel No. 54 are channels listed closest to a channel No. 53, i.e.,channels most adjacent, they have the highest preference.

If a channel No. 51 is in an upper adjacent screen boundary 480 and achannel No. 56 is in a lower adjacent screen boundary 470 are channelslisted next closest to the channel No. 53, they have the next highestpreferences after the channels No. 52 and No. 54.

If an upward search direction is determined by default, channels aresearched for in the sequence of No. 53, to No. 52, to No. 54, No. 51,and No. 56. In this instance, an upward search is conducted prior to asearch in the downward direction. That is, a search is alternatinglyexecuted in an upward direction and a downward direction with the upwardsearch being executed first.

EPG information for each channel is stored in the memory unit 126 assoon as it is obtained, and the microprocessor 124 writes a new programlist referring to this information and provides the new program to theOSG mixer 118, in steps S330 and S340. As a result, new program lists asshown in FIGS. 4B and 4C are sequentially displayed.

The sequence in which the EPG information is listed in the memory unit126 is determined by a typical channel number. Also, when a channel hassubchannels, the subchannels are listed after the main channel.

Accordingly, the microprocessor 124 already knows the listing sequenceof the EPG information stored in the memory unit 126, and also knows thechannel viewed before the program guide mode, to determine one searchsequence.

The sequence for searching for channels may not be determined accordingto adjacency (or proximity). For example, channels may be searched forupward or downward based on the channel viewed before the program guidemode. However, considering the response to the user, it is more properthat the channel search sequence be determined according to theadjacency between channels instead of just to those closest to thechannels shown in adjacent screen boundaries 470 and 480.

The channel search sequence may be changed by the search preference of auser. For example, if a user manipulates the channel up/down button 430referring to a screen shown in FIG. 4C, a continuous search in adirection to be indicated later can be expected. Thus, when a channel upoperation is indicated, the channel search operation may be limited toupper channels instead of just to those closest to the channel shown inadjacent screen boundaries 470 and 480.

The channel search sequence can be determined referring to past viewingtendencies of users. This determines the probability that a channel isto be tuned based on the accumulated frequency of channels tuned by auser. A channel having a higher probability is searched for earlier.

In a storing step S330 of FIG. 3, the obtained EPG information is storedin the memory unit 126. Here, the obtained program guide information canbe renewed only when there is a difference between the obtained programguide information and program guide information stored in the memoryunit 126.

The obtained EPG information is stored in the memory unit 126. Since theEPG information is transmitted by channels, the microprocessor 124acquires EPG information of a corresponding channel whenever a channelis changed, and stores the acquired EPG information in the memory unit126.

A program list is displayed, in step S340.

The microprocessor 124 accesses the program guide information stored inthe memory unit 126 to generate the program list as shown in FIGS. 4Athrough 4C. The program list generated by the microprocessor 124 isdisplayed on a screen via the OSG mixer 118.

The program list is controlled according to a channel up/down command orpage up/down command from a user, and when a channel selection commandis applied by the user, the program of a selected channel is displayed,in step S350.

According to the program guiding method of the present invention, thelonger it takes for a user to refer to the program list, the programguide information of more channels can be obtained. However, the programguide information of channels immediately required by a user can besufficiently acquired even in a short searching time.

According to the method shown in FIG. 3, while a program is selectedreferring to the EPG information displayed by a user, accessiblechannels are scanned in a background operation unnoticeable to a user,thus obtaining the EPG information. Also, the EPG information isobtained referring to the search direction of a user, thus accomplishinga smooth interface with the user.

Furthermore, in order to obtain the program guide information, theprogram guide information of a preferential channel is obtained firstand provided to a user. Therefore, a user does not need to wait untilthe program guide information of all the channels is obtained,increasing convenience.

In the program guide method shown in FIG. 3, the program list as shownin FIG. 4C may be displayed in the display step S310. This is the casewhen a program list including a channel viewed before and channelsadjacent to the channel is displayed in the initial stage of a programguiding operation.

According to an advanced television standard committee (ATSC) standard,the EPG information is recommended to be transmitted in a quantity of atleast 8 hours to a maximum of 584 hours, at time intervals of 3 hours.Thus, erroneous program guide information is less likely to be displayedif a program guide command is performed within 384 hours at maximum.

Accordingly, it is acceptable to display the program list including achannel viewed before the program guide mode and several channelsadjacent to the channel.

However, a program may be changed by the circumstances of a broadcastingstation, or unstored program guide information may be requested. Thus,it is preferable that channels are searched for by the above-describedsearching method even after the program list including the channelviewed before the program guide mode and several channels adjacent tothe channel is displayed, to again obtain a program guide.

Meanwhile, when the program list including the channel viewed before theprogram guide mode and several channels adjacent to that channel isdisplayed in the initial stage of the program guide operation, possibleerroneous information of some channels can be replaced with correctinformation by searching for channels using the aforementioned searchmethod.

FIG. 5 is a block diagram illustrating the configuration of a programguide apparatus according to the present invention. As shown in FIG. 5,the apparatus includes a tuner 50, a ROM 52, a program guide informationdetector 54, a memory 56, a key input unit 58, a microprocessor 60, andan OSD generator 62.

The tuner 50 is tuned to a broadcast signal of a tuned channel. Theprogram guide information detector 54 detects EPG information from thebroadcast signal of a channel tuned by the tuner 50. The detected EPGinformation is stored in the memory 56.

The microprocessor 60 writes a program list from the EPG informationstored in the memory 56 according to a program stored in the ROM 52, andprovides the program list. to the OSD generator 62. The OSD generator 62converts the program list written from the EPG information stored in thememory 56 into a character signal to display the program list to a CRT64.

The microprocessor 60 controls tuning of the tuner 50 in the backgroundoperation while the program list is displayed on the CRT 64, i.e., whilethe viewer does not watch any broadcast program via the tuner, to obtainEPG information of the accessible channels.

The microprocessor 60 searches for channels in a programmed channelsearching sequence. This channel searching sequence depends on thesequence of channels which are displayed in the program guide mode.

When the channel up/down command is input via the key input unit 58during channel search, the microprocessor 60 changes the channelsearching sequence referring to the, input channel up/down command.

When the EPG information is not stored in the memory 56, themicroprocessor 60 generates a message of “please wait” or “acquiringguide information”. When at least a current channel and current programguide information are obtained, the microprocessor 60 generates aprogram list corresponding, to the stored program guide information.

FIG. 6 is a block diagram illustrating another embodiment of a programguide apparatus according to the present invention. Units shown in FIG.6 performing the same operations as those in FIG. 5 are referred to bythe same reference numerals, and will not be described again. Theapparatus of FIG. 6 further comprises a probability estimator 64 inaddition to the components of the apparatus of FIG. 5.

The probability estimator 64 accumulates the number of times channelsare tuned (or selected) by a user, and calculates the probability thateach channel will be selected, according to the accumulated value. Itcan be estimated that the probability of selecting a channel is high asa channel is selected more often.

The microprocessor 124 determines the order of priority of channelsearch according to the probability calculated by the probabilityestimator 64.

In the program guide information acquiring method according to thepresent invention as described above, while a viewer does not watch theprogram of any channel tuned in a tuner, program guide information ofaccessible channels is obtained in a background operation. Therefore,the program guide information of the accessible channels can be obtainedby only a single tuner.

Furthermore, in the program guide method and apparatus according to thepresent invention, information immediately required by a user isobtained first, and information of less preferential channels isobtained next, thus smoothing the interface with the user.

What is claimed is:
 1. A method of channel searching for a digitaltelevision receiver, the method comprising: receiving a transport streamincluding audio, video and additional information, the transport streambeing transmitted from each of broadcast stations accessible in thereceiver; obtaining the additional information from the transportstream, the additional information including Program SpecificInformation (PSI) table data conforming with an MPEG standard;generating a channel list based on the additional information, where thechannel list is made up of one or more separately identifiable channelgroupings, each having one or more two-part channel numbers, where eachof the one or more two-part channel numbers includes a main channelnumber as a first part and a sub-channel number as a second part, andwhere each two-part channel number of a respectively identifiablechannel grouping has a same main channel number and differentsub-channel numbers; and enabling a user to navigate the channel list tosearch a two-part channel number, wherein the navigation of the channellist is performed in a two-dimension numerical order, between two-partchannel numbers of a channel grouping or between channel groupings, andwherein the obtaining of the additional information comprises creatingprogram guide information for a channel that has no program displayed,by scanning accessible channels in the transport stream.
 2. The methodof claim 1, wherein the two-part channel numbers of the channel groupingare collectively displayed in a same direction with a channel groupingidentifier representing the channel grouping.
 3. The method of claim 1,further comprising: receiving a command to navigate the channel list;and displaying plural channel grouping identifiers and/or pluraltwo-part channel numbers in the two-dimension numerical order.
 4. Themethod of claim 1, wherein the two-part channel number represents anidentifiable program based on predetermined identification informationunique to a program according to the MPEG standard, and a relationship,according to an ATSC standard, between the two-part channel number andthe predetermined identification information unique to the program. 5.The method of claim 1, wherein the channel list is navigated in a firstdirection between the two-part channel numbers of the channel grouping,and navigated in a second direction between the channel groupings. 6.The method of claim 1, wherein the channel list is designed to be shownin a single display window, where the window is vertically andhorizontally embedded with two-part channel numbers.
 7. The method ofclaim 1, wherein the navigation of the channel list is performed in thetwo-dimension numerical order on the single display window, where thewindow is vertically and horizontally embedded with two-part channelnumbers.